Electromagnetic switch



Jan. 11 1927.

| M. ASPINWALL ELECTROMAGNETI C SWITCH Filed Nov. 2, 1921 5 Sheets-Sheet 1 WITNESSES: INVENTOR Jan. 11, 1927.

L, M. ASPINWALL.

ELECTROMAGNETIC SWITCH Filed Nov. 2. 1921 :s sheets-sheet s R O T N E V W WITNESSES: ZR,.2.?%M

[Hula/Z Lau/ls MAS ATTORN EY Patented Jan. '11, 192?.

UNITED STATES LOUIS M. ASPINWALL, OF PITTSBURGH. PENNSYLVANIA, ASSIGNOR TO WESTING- HDUSE ELECTRIC &- MANUFACTURING COMPANY, A CORPORATION OF PENNSYIF vnnm.

ELECTROMAGNETIC swrrcn.

Application filed November 2, 1921. Serial No. 512,182.

My invention relates to switches and it has particular relation to Switches for governing circuits lSI'YlVGlSQKl by moderately heavy currents.

One object 01 my invention is to prov de an improved switch mounting whereby the switch may be readily installed and removed and'be readily accessible to inspection.

Another object oi my in vention is to proride means for securing an initial pull between a p0le-piece and an armature member of a switch that shall be much higher rela tive to the holding force, when the armature member is in contact with the pole piece, than is ordinarily obtained in switches of this character A third object of my invention is to provide an improved method of organizing the parts of a switch that will insure the contact members being in proper relation, the one to the other, when'the switch is assembled.

Briefly speaking, my invention consists in employing a plurality of terminals of a switch to support it in a partially suspended position, in so'organizing the pole-piece and the armature and its mounting that only a relatively small portion of each of the adjacent surfaces thereof may be brought into contact and in securing the stationary contact member to the casting upon which the movable contact member is pivotally mounted, thereby avoiding the necessity of having precise distances, between centers of bolts, that would otherwise be employed to mount the arts upon the base member of the 'switc F0r a better understanding of my invention. reference may be made to the accompanying drawings,

Figure 1 of which is a view, partly in side elevation and partly in section, of a. switch mounted upon a car; 1

Figs. 2 to 4, inclusive, are views, in bottom plan and in side and end elevation, respectively, of the switch that is illustrated in Fig. 1 of the drawings;

Fig. 5 is a view, in perspective, of a casting constitutini a part of the switch that is illustrated in figs. 1 to 4 of the drawings; and

' Figs. 6 and 7 are views, in side elevation and in plan, respectively, of the pole-piece and armature member of the switch illustratcd in Figs. 1 to 5, inclusive, of the drawings.

Referring particularly to Figs. 1 to 4 of the drawings, a switching device 1, which is provided with a base mei'nber i2 and two like circuit terminals :5 and 4, is mounted in a car 5, adjacent to the roof 6 thereof, partly by means oi" a plurality of stationary supporting meinl'iers 7. The members 7 are spaced, the one from the other, by means of a block The remaining siniportingr means for the switching device constitutes the terminals lauil 4, which are slitlably mounted upon a plurality of rigid coniluctingincur hers 9. The members 9 are mounted upon a stationary insulatingmember 11. y

, The terminals 3 and 4, which serve a twofold purpose: first, to conduct electricity, and, second, to support the switch 1, are mounted upon the conducting members 9 by means of a plurality of nuts 12. The conducting members 9 are connected directly to a plurality of conductors 1.3, which constitute parts of the control system.

The supporting member 11 is mechanh cally connected to one of the frame menibcrs 14, constituting a part of the root 6 of the car 5, by means of :1V plurality of metallic straps 15 and bolts 16. An insulating member 17, made preferably of asbestos board is mounted in front of the terminals 3 and 4, of a plurality of switches 1, by means of an angle member 18 and a plurality of bolts 19.

A. strip of insulating material 9.1 is sooured to the base member 2, and, extending parallel to the asbestos front member 17, serves to more rigidly maintain that member in .osition.

be stationary supporting members 7 and the block 8 are maintained in position by being secured to a clip angle member 23 by a plurality of bolts 24. The clip angle mem ber 23 is secured to the side sheet 25, constituting a part of the car 1, by means of bolts or spot welding.

To inspect or remove the switch 1, it is necessary to remove only a cover member 26 and the asbestos board 17 to secure access to the bolts '12, which maintain the terminals 3 upon the stationary conducting members 9. After removing the nuts 12, the switch 1 may be pulled outwardly toward the center of the car 5, thereby disengaging the base member 2 from the bifurcated support; formed by the stationary members 7 and the block 8. A roof ventilator 26/ is provided to permit air to circulate about the H\\'lll.ll0b 1.

bolts 31- An arch shield 32 is provided for protecting the magnelizablc member 27 from any arc that may be established between the contact members of the switch which are hcreinat'ler described. A stationary control linger 33 is secured to the cross piece :29 by means of a relatively flat member 35 and a tap bolt 34.

The member 27 also provided with a plurality of' projecting arms 36 on which a lever arm 37 is pivotally supported by means of a pin 38.

The pirotally mounted arm 2 is provided with a plurality of projecting arms 39, on which a movable supporting and conducting member it! is pivotally supported by a pin ll. A movable control linger -12 is secured to the supporting member 40 by a tap bolt i301. lhc arm 37 is biased to its lower posilion by mcans ot' a spring ll}. The movable control linger 1-2 is biased to the position illustrated in the drawing by means of a resilient member ll.

The control lingers 33 and 42 are provided with are horns l5 aml 46, respective l}. A magnetic blow-out device, for extinguishing an arc that may be established between the control fingers 83 and 42 upon their assuming an open position, comprises a plurality of polc-pieces 47, which are mounted upon an arc box 48, a magnetizable pole member 49 and a coil 51. r

The magnetizable member or casting 27 has a core member 52 moil'nted therein, which is surrounded by a magnetizing coil 5.). having a plurality of terminals 53a. A stationary pole-piecc 54 is mounted upon the core member and may be engaged by an armature member 55, which constitutes a part of the lever arm 37.

For a better understanding of the movement of the arn'iature member 55 in relation to the pole-piece 5st, reference may be madeto Figs. 6 and 7 of the drawings, which are views, in side elevation and in plan, respectively. The pole-piece 54 and the armature member 55 are triangular in shape and are of substantially the same size. When the pole-piece 54 and the armature member occnpy the positions illustrated by the solid lines of Fig. (5 of the draw logs, the adjacent surfaces thercol are situated directly opposite each other.

Upon the armature member 55 being artnatcd to its closed position, which is illus trated by broken lines in vFigs. (i and 7 ol the drawings, the adjacent surfaces of the pole-piece 514- and the armature member I)? are in oil'sol relation, the one to the other. ln other Words, much snaillcr active areas of the polwpicco iii and the armature incinllcr 55 are employed to maintain the switch in its closed position than are employed l'or closing, the switch. nile-piccc Set and the armature member 55, the pull el'l'ected thcrel'iy to close the switch and the pull cllccted thereby to maintain the switch in its closed position are more nearly equalized. l nl pull exerted by the magnet has a greater alue relative to the holding force for maintaining the switch closed than has been securel previously by switches of this charactor,

The operation of the switch 1 is elicclcd by energizing the coil 51, by means of an auxiliary circuit comprising the terminals Fill/1 Upon the cncrgization of the coil 53, a magnetic circuit, comprising the core mombcr 62, magnctizablc casting 2T, lever arm 37, armature member and stationary polepicrc M, is energized to eil'cct upward moveuu-ut ol' the lever arm 37.

The lever arm 3? will more upwardly until the arnuiturc member 55 engages the staticnary pole-piece 54-. Prior to this engagement, the control linger 42 engages the stalilillltll'y control finger 33, thereby establishing a circuit from the terminal 3 ot the switch 1 through the magnetizing coil 51, metallic holding member 35, stationary control'fingcr 33 movable finger 42, lever arm 37, shunt member 56, and conductor 57 to stationary contact. terminal l.

lVhen the control fingers 33 and 42 are separated, the are established thercbctwccn is extinguished by the flux from the magnotic circuit, comprising the pole member 49 and the pole-pieces 47, which are energized by means of the blow-out coil 51.

From the above description, it is apparent that I have provided relatively simple means for mounting a switch by means of its contact terminals and a bifurcated supporting structure in which the base portion of the switch is slidably mounted. By haviug both of the control lingers secured to the casting 27, I have provided means for preventing the control lingers from occupying in'iproper positions in their relation, the one to the other, because of incorrect disl'ly this design of the in other words, the iuitanccs between the centers of the supporting bolts when the control fingers are mounted separately on the base portion of the switch.

I have also provided means for insuring a relatively higher initial pull for closing a switch than is secured by uppa'atus eonslructed in accordance with the prior art.

"hilc l have shown the switch in its preferred form, it is apparent that minor mo li li'cutions may be made in the arrangement ol'- parts without departing from the spirit of my invention. I desire, therefore, to be luuiled only by the scope of the appended claims.

I. clnim as my invention 1. in a switch, the combination with a plurality of magnetizable i'nembers of triangular shape, oi means for so mounting said members that they occupy positions sub-- stantially opposite each other under one circuit condition and are in oii'set relation Ull- (icr another circuit condition.

L. In a switch, the combination with a plurality of triangular magnetizable members, of a pivotal support for one of said members that is otl'set from the plane of contact oi said members.

23. In a switch. in combination, switching members operable to make and break electric circuits and mugnetizable members for closing said switching, members, said magnetizeble members being disposed to efi'ect a. transverse relative movement during operntion to vary the cross-sectional area of the i'nagnetic path thereby to control the magnetic attraction between said members.

i. In a switch, in combination, switching nngmbers operable to make and break electric circuits, magnetizable members for closing said switching members, said magnetizable members being disposed to eil'ect it trnnstnating the switch members, contacting faces 7 on the nmgnetizuble members, said provided magnetizable members being disposed for operation to move the contacting laees transversely oi. one another to effect the setting of St-titl contact faces in alinement when the switch members are open and in overlupping; positions when the switch members are closed, thereby to control the magnetic nit.- truction between said members.

6. In. a switch, in combination, magneticable members for iu'tunting the switch, triangular contacting faces provided on the magnciizable members, said megnetiznble members being, disposed for operation to move the triangular faces transversely of one another to cited the setting of said con tact faces in alineinent when the switch members are open and in overlapping posi tions when the switch members are closed, thereby to reduce the magnetic attraction be tween said switch-actuating members as they move toward one another.

In testimony whereof, I have hereunto subscribed my name this ifi tth day of O0 tober, 1921.

LOUIS M. ASPINVVALL. 

